Patients with antisocial personality disorder incur high costs on society, and are at high risk of dropping out of treatment and are often excluded from treatment, yet very little research has been conducted on how to best help these patients.

To test a six-session psychoeducation program, Impulsive Lifestyle Counselling, in outpatients with substance use disorders and antisocial personality disorder.

To test the efficacy of the intervention versus treatment as usual in community outpatient treatment for substance use disorders.

Pragmatic randomized trial in 13 outpatient community substance abuse treatment uptake areas. Patients were interviewed by blinded interviewers 3, 9 and 15 months post-randomization and tracked through a national substance abuse treatment register. Mixed effects regression were used to assess substance use and self-reported aggression and Cox regression was used to assess risk of dropout.

A total of 175 patients was randomized. At 3-month follow-up, patients randomized to intervention reported more days abstinent and less drug use severity than patients randomized to treatment as usual. In addition, patients randomized to intervention were at lower risk of dropout after intervention. In addition, patients randomized to intervention were more likely to report having received help for antisocial personality disorder at follow-up interviews.

A brief psychoeducational intervention may improve outcomes for outpatients with antisocial personality disorder.

The authors have not supplied their declaration of competing interest.